Cause or Effect in Effort Control: A Fundamental Question for Cod Recovery

20 September 2010

Fisheries scientists at the recent seminar on the state of European fish stocks, in Brussels, drew attention to the “strong correlation” between the dramatic fall in KWdays used by the North Sea demersal fleets and a similar downward trend in fishing mortality (F) since 1999.

An inference from this correlation could be that days-at-sea restrictions have been successful. The thinking at the heart of the current EU Cod Recovery Plan is that as effort control is applied progressively and the fleets are forced to cut their time at sea to comply with the legal constraints, the catch of cod will be reduced – and a corresponding fall in mortality shows up in the annual assessments.

But is that what is really happening?

An alternative picture can be painted to explain what has really happened if we look below surface appearances. Reduction in Fleets/ Reduction in kWdays/ Reduction in Fishing Mortality

First, in looking at this graph it is highly significant that the first cod recovery plan, and along with it effort control, first came into effect only in 2003, whereas the fall in mortality and KW days appears to begin around 1999. This partly reflects the reasonably strong 1996 year-class but also correlates with the impact of major fleet reduction programmes in the North Sea.

The biggest cod catching member states in the North Sea are the UK and Denmark. Before and after 2002 both countries implemented huge, publically-funded, decommissioning schemes that reduced fishing capacity – especially fishing capacity targeted at cod, on a very significant scale. The evidence, for those interested in looking beyond statistics, is very visible in the empty quaysides and harbours around the North Sea.

Although primarily flatfish fleets (and therefore only taking cod as a by-catch), the Dutch and Belgian fleets have also been subject to large scale capacity reduction through decommissioning.

If the fundamental origin of the problem facing the North Sea cod stocks was the expansion of fishing capacity in the 1970s and 1980s on the back of the gadoid explosion1 (fuelled also by the availability of EU and national construction and modernisation subsidies), the antidote has largely been seen in the publically-funded decommissioning schemes of the 1990s and after 2000.

If this interpretation is correct, then both the fall in KW days and fishing mortality are both, in large part, consequences of capacity reduction. Boats that have been scrapped don’t clock up days at sea. Neither do they kill cod. In other words, the reduction in Kwdays can in substantial part be attributed to a reduction in the number of vessels.

More Drivers

Of course reality is never straightforward. Over the same period, 2002 -2007, other factors were in play:

The tightening of landing controls on the demersal fleets through a range of measures including designated ports and in the UK, the registration of buyers and sellers, which for the first time created sanctions for those providing a market for over-quota or misreported fish.
Highly restrictive quotas, enforced with increasing rigour over the period
An increase in legal mesh size for vessels targeting large bodied demersal fish like cod from 100 to 120mm
A range of other technical requirements such as maximum twine thickness to improve the selectivity of nets
The combined effect of the much tougher regime for whitefish led a large part of the whitefish fleet to redirect their efforts to other species such as Nephrops (prawn) and monkfish.
Probably one of the least successful measures was the seasonal closure in 2001 of some 400 square miles of what was deemed to be spawning grounds, which the scientists subsequently assessed to have done more damage than good
Effort control, applied under the 1st cod recovery plan from 2003 -2007. At the end of that period the days -at-sea regime was deemed to have failed because of the “headroom” it provided between fleet activity and available days and the derogations necessary to make the blanket approach work.
Under the economic pressures of cod recovery measures, the diversion of a large number of vessel from the white fish fisheries into fisheries where cod is a small by-catch – notably the Nephrops (prawn) fisheries
Finally, from 2009 onwards, a revised cod recovery plan with based on allocations of effort (Kwdays) to member states, automatic TAC and effort reductions determine by the presumed state of the stocks and the level of fishing mortality and with limited opportunities to “buy-back” effort through various cod avoidance measures

It will probably never be possible to untangle the relative contribution of all these combined measures to the reduction in the fishing mortality of cod witnessed after 1999. It is however vital, as we move forward not to confuse correlation with causation, not leastbecause deciding on the role that effort control has, or has not, played in achieving the observed fall in fishing mortality of cod is the utmost importance for the future of the EU Cod Recovery Plan, which will be reviewed in 2011.

Rebuilding the Cod Stocks: alternative approaches

If this was just a question of semantics or arcane debate between academics it would matter little. However, the question of whether effort control has been an effective means of reducing fishing mortality in the cod fisheries is a fundamental question that carries consequences for a large number of fishermen, ancillary trades and their communities. The future of the cod recovery plan, due to be reviewed next year, the future direction of the cod stocks and the future of the fleets depend on it.

If the answer is yes, then the industry can look forward to more of the automatic year-on year reductions in effort (days-at-sea) that has characterised the current cod recovery plan. If the answer is no, then the future lies in continuing to create the conditions for rebuilding of the cod stocks through various kinds of incentivised cod avoidance measures. Real time closures and catch quotas have shown real promise but are only effective if the right incentive structures are in place.

The attractions of effort control for the Commission are plain. In a centralised, top-down management regime, effort control represents a simple lever that can be pulled once a year and fishing mortality will fall accordingly – a bureaucrat’s dream. The direct experience of effort control however suggests something different. Even the use of the words “fishing effort” is full of ambiguity both in fisheries science and more generally by fisheries managers.

For the Commission, fishing effort means fishing capacity x time at sea. In ICES science the words are used differently in different contexts but on the whole they mean the totality of fishing activity (fishing capacity x time at sea x fishing behaviours or fishing strategies).

It is the behavioural aspect of fishing that makes effort control a poor instrument for the cod fishery. Fishermen on the whole act in economically rational ways and this means that fishing strategies adapt to take account of effort constraints. This can mean;

For vessels that are short of days to fulfil their fishing strategies, the transfer or purchase of kWdays from less active vessels
Fishing more intensively during the time allowed at sea – “capital stuffing” or technological response
Making full use of 24 hours in the day whereas previously the average was much lower
Shortening steaming times
At least one hundred or more other strategies to maximise fishing intensity and reduce consumption of days, chosen to suit each individual vessels circumstances

The fisheries response to effort control is fundamental to the success or failure of effort limitation as a way of rebuilding the cod stock, yet so far it has been almost completely ignored by ICES and STECF2, no doubt because it is easier to measure a KWday than to assess the impact of diverse fishing strategies. Economic incentives are at the heart of what drives most businesses and it seems perverse to ignore their effect in achieving conservation objectives, yet this is what has been done in EU fisheries policies for 20 years.

So who is right? The Commission and those scientists whose data suggests to them that effort control is a simple and effective tool; or those who point to capacity reduction and landing controls as the primary drivers of both the reduction in KWdays and fishing mortality?3

The Brussels Seminar at which Commissioner Damanaki exhorted us to accept the science as the starting point for fisheries management served an important purpose. It showed the underlying trend towards improvements in many European fish stocks. It also laid bare the belief within the Commission and amongst some scientists that effort control is an effective tool. This allowed the fishing industry the opportunity to question whether current policy on cod is based on a statistical correlation between falling KW days and reductions in fishing mortality to which a spurious causality has been attributed.

Our points have not been lost and an important STECF working group has been convened to meet towards the end of September to provide advice on the fishing effort regime. Its terms of reference include the question: what is the relationship between fishing effort and fishing mortality. Much hangs on the answer to that question.

Effort and Discards

A secondary justification advanced by the Commission for effort control is that a cut in effort (time at sea) has resulted in a reduction in discards in the plaice and haddock fisheries. But again to our mind, the Commission is misattributing cause and effect. The reduction of discarding in the plaice fisheries is likely to be closely related to the reduction in the number of Dutch and Belgian beam trawlers, following major decommissioning schemes, which of course results in a decrease in deployed fishing effort. And it is not necessary to go much beyond the mesh size increase from 100 to 120mm to explain the observed reduction of discards in the haddock fishery.

As for cod, the application of effort control in 2008 and 2009 coincided with a massive increase in discards. It is not difficult to see that the main reason for this is that EU and Norway have elected to set TACs towards the lower levels of the recommended catch options provided by ICES.

All this draws attention to the tenuous scientific justification for effort control, the weak correlation between effort reductions and reductions in discards and the need for a fundamental re-evaluation of the EU approach to cod recovery.

The gadoid explosion or gadoid outburst was a massive, largely unexplained, increase in almost all gadoid stock, in the 1970s. The gadoid stocks, including cod, haddock and whiting, rose to levels much higher than had been seen in the rest of the 20th century. Some explanations have linked it to the low level of herring stocks –a major predator- at the time – but environmental factors are also likely to have been involved.
It is only fair to point out that STECF does not set its own agenda, as the Commission through terms of reference shapes and controls STECF’s focus
The unexpected increase in fishing mortality of North Sea cod in this year’s ICES advice is being challenged and will be looked at again in the October advice. In any event, at the Brussels Seminar the point was made that it is wise not to over-interpret one year’s assessment but rather to look at long-term trends. It is interesting that the Commission has suggested that the incentivised cod avoidance measures such as real time closures could have undermined the effectiveness of the effort regime since 2007. The opposite argument could be more valid: that the scale of reductions under the effort regime, and a half -hearted approach to incentivising cod avoidance measures have undermined the potential of the latter.